Myth: The Solomon Amendment doesn't apply to universities since they didn't formally expel ROTC
Instances of this myth: New York Times op-ed, Boston Globe editorial, Yale Herald blog post and a Medill News Service article in the Army Times.
Facts: The Solomon Amendment is written with robust language to apply to a college if:
that institution (or any subelement of that institution) has a policy or practice (regardless of when implemented) that either prohibits, or in effect prevents - (1) the Secretary of a military department from maintaining, establishing, or operating a unit of the Senior Reserve Officer Training Corps (in accordance with section 654 of this title and other applicable Federal laws) at that institution (or any subelement of that institution); or (2) a student at that institution (or any subelement of that institution) from enrolling in a unit of the Senior Reserve Officer Training Corps at another institution of higher education.
The fact that universities effectively barred ROTC by the indirect means of withdrawing the conditions specified in the ROTC Vitalization Act of 1964 is not important from a legal perspective since this "in effect prevents" ROTC.
The fact the some universities have cross-town ROTC opportunities (provision 2) does not render it in compliance with the law if the university effectively bars on-campus ROTC (provision 1).
The Solomon Amendment has not been invoked for ROTC since it can be invoked only by the Secretary of Defense, who has not invoked the law for ROTC. In contrast, the Solomon Amendment has been invoked for military recruiting, and the Supreme Court ruled unanimously that doing so was constitutional for military recruiting. However, the ruling noted that "recruiters are not part of the law school", drawing a contrast to the situation on ROTC that leaves it unclear how the court would rule on an ROTC-related Solomon Amendment issue. This uncertainty, together with the "shotgun wedding" nature of using the Solomon Amendment to force an ROTC program onto a campus, account for some of the reluctance of the Bush and Obama administrations to apply the Solomon Amendment to ROTC.